Coal screw conveyer



B. B. NELSON ET Al'.

COAL SCREW CONVEYER March 7, H950 2 Sheets-Sheet l Filed April 17, 1946 CIT B. B. NELSON ET AL,

COAL SCREW CONVEYER 2 Sheets-Sheet 2 Filed April 17, 194e Patented Mar. 7, 1950 COAL SCREW CGNVEYER Bradford B. Nelson, Aurora, Ill., and James H. Nelson, Ladoga, Ind.; said .lames H. Nelson assignor to said Bradford B. Nelson Application April 17, 1946, Serial No. 662,702

7 Claims.

This invention relates to a conveyor for moving loose material such as coal, and in our reference hereinafter to coal as the material upon which the present machine may operate, we would have it understood that we include also other lumpy or granular materials as well.

In particular, the present improvements are directed to a conveyor which will move coal from within a building to a point exteriorly thereof, or from one point in a building to another interiorly thereof, or from one point to another both outside of any building. The coal to be moved may be piled in a bin or in a yard, and be shifted by the present conveyor for the full distance of its capacity, the original pile of coal being substantially completely removed in the operation. Coal of various sizes and `grades may be handled by the present conveyor with little or no diiculty as the result of the special improverments hereinafter noted. The features of our invention may also be embodied in a mobile unit that may be propelled from place to place, thereby adapting it to be moved from one pile to another.

Certain exempliications of our invention are set forth in the accompanying drawings in the manner following:

Figure 1 is a side elevation of the conveyor shown as extended within a building one of whose walls and the floor is indicated in section, the conveyor being extended also to a point exteriorly of the building where the moved coal is to be deposited;

Fig. 2 is a plan view of the conveyor;

Figs. 3, 4, and 5 are transverse sections taken, respectively, on lines 3 3, 4 4, and 5-5 of Fig. 1;

Fig. 6 is a View in plan of the conveyor housing having the construction that is preferred for that part thereof which is remote from the original pile, or exteriorly of the building, as indicated in Figs. 1 and 2; y

Fig. 7 is a transverse section, taken on line 'l-'l of Fig. 6;

Fig. 8 which is a View similar to Fig. 6 shows a somewhat shorter conveyor housing construction slightly modied to meet a changed condition;

Fig. 9 is a vertical section through a conveyor housing whose construction is further modified;

Fig. 10 is a transverse section, taken on line lil- I0 of Fig. 9;

Fig. 11 is a sectional detail in perspective showing the gate operating means elsewhere illustrated in Figs. 9 and 10;

Fig. 12 which is a view similar to Fig. 10 shows a modication of the mechanism therein illustrated;

Fig. 13 is a side elevation of a conveyor forming part of a mobile unit adapted to be propelled to the place where the removal of coal is to be performed; and

Fig. 14 is a detail in section, taken on line lil-i4 of Fig. 13.

Our conveyor comprises an elongated feed screw S whose spiral flights I5 are carried by a shaft l5 adapted to rotate Within a U-shaped tubular housing. This housing comprises at least two sections joined end to end, one desighated as A, being located usually within or beneath the pile to be removed, and the other sec-V tion B in the clear therebeyond. As shown clearly in Fig. 1, these two housing sections which differ `from each other in various details of construction are separated by a connecting plate I8 to be further described hereinafter.

The Walls I9 of the buried housing section A are in the form of a semi-circle (see Fig. 3), except at the end 20 where they may be extended continuously through 360, and at spaced points, perhaps four feet apart, where for a distance of about a foot they are extended upwardly and toward each other in the form of gates 2|, each having a convex contour spaced from the other by a couple of inches or so at the narrowest point. The feed screw S which is mounted within the housing is confined lin place therewithin by these gates, and the material that is fed lengthwise by the screw through the housing is guided and metered by the gates.

At a point which is beyond the pile the housing joins with the connecting plate i8 (see Fig. 5) wherein is an openingl o traversed by the feed screw which is extended on into and lengthwise of the exposed housing section B. This plate extends up somewhat above the housing section A for connection with the section B whose proximate end may be formed with an outturned flange 22 for this purpose. The opening o provided in this plate is the same in size and shape as the chanel that is formed within the housing section B Whose walls 23 extend straight upwardly, and for a substantial distance, from the round bottom of the housing. At the top of these walls outturned anges 24 may be provided for support of cover plates 25, one or more of them, which are thereby maintained in a xed position above the feed screw S with a substantial clearance there between. The cover plates will ordinarily be fastened in closure` position, as by means of suitable bolts, although for clarity of illustration they are shown as removed in Figs. 2, 6, 7 and 8.

Opposed retainer bars 26 may be carried by the housing walls 23 adjacent the feed screw (see Fig. 7) these bars being preferably curved in cross-section to follow the contour of the screw whereby to closely guide the loose material that is propelled thereby through the housing. If desired, the bolts 21 which secure these retainer bars in place may be entered through vertical slots in the housing walls 23, so as to provide for a slight adjustment in the position of these bars. toward and from the feed screw, as desired. Experience has demonstrated the advantage of having each retainer bar about ten feet long with an endwise spacing between them of no greater length. This is illustrated clearly7 in Figs. 6 and 8 in which the exposed retainer bars are shown as located medially of the housing B whose lengths are indicated as about 30 and 20 feet, respectively.

According to our invention, it is possible to pron vide for a change in the direction of the coal undergoing movement, this being accomplished with the aid of certain unitary mechanism which may include the motor which drives the feed screw S. For this purpose we arrange at the end of the housing B, at a lower elevation, another tubular housing C, the one being extended angularly of the other. A discharge opening 29 is provided in the bottom of the housing B adjacent its end to permit the ori-coming coal to descend through a conduit 3U intothe end of the housing C therebelow to be engaged and propelled for wardly by a feedscrew S therewithin. The axis of this conduitis the center `about which swinging movement of the housing C may take place. The feed-screw inthe housing C, which is substantially the same in construction-as the one first described, comprises a shaft 3i which a-t one end is journaled in a bearing 32, a sprocket'wheel 33 being carried fast on the shaft at a point slightly ,beyond the proximate end 34 of the housing C. A chain belt 35 runs over this wheel and also a second sprocket wheel 36 at the end of a jack shaft 31 which is journaled to rotate in a. frame `38 that is carried by the housing C to oneside thereof. The jack shaft which is transversely divided is provided with a connecting shear coupling 39 between its two sections. this coupling including a key which is entered within a. spline in one section whereby to permit axial movement-oi` one section toward or away from the other without disturbing the driving connection therebetween. The jack shaft extends lengthwise of the housing C at an elevation which coincides with that of the shaft I5, and at about the point of intersection thereof the shafts IE and 31 are provided with intermeshing bevel gears 40 and 4I respectively, enclosed within a common exible covering 42 which rotates therewith. In this way we provide, in effect, a universal joint between the shafts I6 and 31, and since the latter is in driving connection with the shaft 3l, thevoperation of both feed screws S will proceed in unison. Power to operate these shafts may be supplied from a motor (not shown) which drives a chain belt 43 ruiming over a sprocket wheel 44 on the shaft I. By this construction we make it possible to swing the housing C about a vertical axis which intersects the center of the conduit 3D to various angular positions relative to the housing B, so as to locate the point of iinal discharge in any one of a number of selected positions.

Referring now to Figs. 9-12,fwe have shown a 75 i construction of the housing B which differs in the respect that the retainers therein are in the form of plates hingedly mounted so as to be adjustable toward and from each other, or toward and from the opposite wall, whereby to vary the clearance therebetween.

According to Figs. 9 and 10, there is provided on the inside of each housing wall 23 adjacent its top, a beveled shelf bar 5l! whose inner edge is in hinged connection 5i with a retainer plate 52. These plates which are elongated and arranged end to end (see Fig. 9) are adapted to hang down vertically, as shown in Fig. l0, with a substantial clearance therebetween; or be swung up- 1 wardly to a selected position of adjustment in which case the clearance between the free edges of the retainer plates is somewhat reduced. As a suggestive form of operating mechanism whereby any pair of opposed plates may be independently adjusted. we have shown in connection with each a cylinder mechanism 55 which includes a plunger 56 from which is extended a link 51 having at its opposite end connection with the retainer plate 52 at a point adjacent its free edge.

When the retainer plates are hanging vertically,

the links will be angularly disposed behind each plate and alongside the plunger with which it is connected; but when it is desired to advance .the plate inwardly, the cylinder mechanism, operated by a uid under pressure, is adapted to move the plunger forwardly whereby to swing the link to a more or less transverse position (see Fig. l1) where it is eifective to support the retainer plate in an inward position. No cover plates need be used with this construction nor with the one of Fig. l2 now to be described.

lAccording to Fig. l2, there is provided a single retainer plate e0 hingedly supported at 5I adjacent its top edge to a flange 52 a pair of which is inturned from the top of the housing walls 23. This plate is adapted in its up position to lie horizontally between the inturned anges 62 so as to provide a closure therebetween. The mechanism for operating this closure plate may be the same as that already described, viz. a cylinder mechanism 55 from which is extended a link 51 in operative connection with the plate at a point relatively close to its free edge.

One adaptation of our invention is suggested in Figs. 13 and 14 where we have shown the conveyor built on to a tractor T, and extended forwardly thereof to constitute therewith a mobile unit. The conveyor in this case comprises a tubular 'housing A which may be the same in all essential respects with the one shown in Fig. 1, except that it is externally reenforced by longitudinally extending side ribs S5 and a bottom rib 6B. A bracket connection B1 may be extended from the forward end of the tractor to the connecting plate I8 which is interposed between the forward housing section A and a rearward section B that is carried on the tractor. Extending continuously through the two housings A and B is a feed screw S comprising spiral flights l5 mounted upon a shaft I6 which at its rear end is journaled in a bearing 10. At a point close to 'this end of the shaft we have afxed a sprocket wheel 1l over which is trained an endless chain 12 which runs over a second sprocket wheel 13 aiixed to the end of a power take-ofi shaft 'i4 in connection with the motor 15 which drives the tractor. The material which is propelled endwise through the conveyor is discharged out at the far end of the tubular housing section B through a discharge conduit 16 which may lead laterally or otherwise to a desired point.

The forward end of the housing section A is left open by cutting the adjacent housing walls I9 back at 11 so as to expose the feed screw from both sides as well as at its top. The mobile unit thus constructed may travel under its own power to the place where it is to be used. Also in emergency cases, such as where a pile of coal is burning and cannot be closely approached on account of the heat, a mobile unit such as we have here disclosed may be brought into operative position to remove the burning coal to a point suiiiciently distant to permit extinguishment of the fire as the coal is freshly deposited in its new location.

There are certain problems connected with the mechanical handling of loose materials, such as coal, arising from such factors as the weight and size of the material, its tendency to clog, etc. The behavior of coal which is mechanically removed from a pile may vary according to the conditions there present. We find that it is possible to obtain improved results by the tubular housing here disclosed which is open from end to end and provided at spaced intervals with gates which furnish a sufficient guide for the feed screw and for the coal which is being propelled lengthwise through the housing. At the point where the coal emerges from the pile, we provide another housing section having a different cross-section, in that the walls thereof extend vertically upwardly to support cover plates and/or retainers. In addition the provision of retainer bars appears to be important in order to meter and guide the advancing coal. Between the connected sections is the wall having ar through opening corresponding to the interior of the channel which is defined by the tubular housing B. This is of importance because it provides a means for securely connecting the one section to the other, and at the point vof transition it facilitates the passage of coal therethrough freely and without clogging.

Since in many cases the discharge point for the conveyor should desirably be shifted from time to time, we provide for such a contingency, and with a minimum of effort, by swivelly connecting the housing section B to the housing section C so that the latter may be swung to, and locked in, various positions. While the range of swinging movement may not be great, it is nevertheless sufficient to produce a discharge of the coal at various selected points so that the remainder of the conveyor mechanism may function without any disturbance or interruption. These various adjustments of the housing section C may be made without disrupting the operative connections to the feed screw which is mounted within the housing section C.

We claim:

l. A conveyor for removing piled coal and the like comprising a connecting plate with an opening therethrough, la, pair of round bottom housings arranged end-to-end on opposite sides of the plate and joined thereto, one of the housings adapted for positioning below the pile being open continuously along the top with its walls substantially semi-circlular in cross-section and having opposite portions thereof at spaced intervals extended arcuately toward each other in the form of fixed gates whose confronting edges are narrowly spaced, the second housing adapted for positioning beyond the pile being formed with Walls having portions extending vertically to a point above the top edges of the rst housing and defining therebetween a trough the same in size and shape as the through opening in the connecting plate, a cover affixed to the second housing, and a feed screw extending lengthwise through the two housings and the plate therebetween, confined by the round bottoms of the two housings and by the gates of the first housing for rotation about a fixed axis whereby to propel longitudinally thereof coal entering into the open top of the first housing from the pile thereabove.

2. A conveyor for removing piled coal and the like comprising a round bottom housing adapted to be positioned below the pile and being continuously open along the top with its walls substantially semi-circular in cross-section and having opposite portions thereof Iat spaced intervals extended arcuately toward each other in the form of fixed gates with confronting edges narrowly spaced, and a feed screw extending lengthwise through the housing confined by the round bottom thereof and by the gates for rotation about a fixed axis whereby to propel longitudinally thereof coal entering into the open top of the housing from the pile thereabove.

3. A conveyor for removing piled coal and the like, comprising a connecting plate with an opening therethrough, a pair of round bottom housings arranged end to end on opposite sides of the plate and joined thereto, and a feed screw extending lengthwise through'both housings and through the intervening connecting plate, one of the housings adapted for positioning below the pile being open continuously along the top with its walls substantially semi-circular in cross-section, and having opposite portions thereof at spaced intervals extending upwardly and partially over the feed screw whereby to provide therefor, in conjunction with the round bottom of the housing, a guideway wherein the feed screw is confined to rotary movements about a fixed axis.

4. A conveyor for removing piled coal and the like comprising a round bottom housing adapted for positioning below the pile and being open continuously along the top with its walls semicircular in cross-section and having opposite portions thereof at spaced intervals extended arcuately toward each other in the form of fixed gates with convex confronting edges narrowly spaced medially thereof, and a feed screw extending lengthwise through the housing confined by the round bottom thereof and by the gates for rotation about a fixed axis whereby to propel longitudinally thereof coal entering into the open top of the housing from the pile thereabove.

5. A conveyor for removing piled coal and the like, comprising a round bottom housing extending from a position below the pile out into the open therebeyond, the housing exteriorly of the pile being formed with walls having portions extending vertically :above the round bottom, a cover affixed to the housing, a feed screw extended lengthwise through the housing, and opposed retainer means, spaced apart lengthwise of each other a distance approximately the length of each, carried by the housing walls interiorly thereof in partial overlapping relation to the feed screw and cooperating with the round bottom to confine the feed screw rotations about a fixed axis whereby to propel longitudinally of the housing coal entering into one end thereof.

6. A conveyor for removing lpiled coal and the like, comprising .a round bottom housing extended 7 from a point below the pile out into the open therebeyonma feed screw extending lengthwise through the housing, the housing being provided with walls extending upwardly above the top of the feed screw, and opposed retainer means spaced apart lengthwise of each other carried by the housing walls in partial overlapping relation to the feed screw adapted to cooperate with the housing round bottom in confining rotation of the feed -screw about a fixed axis whereby to 10 propel longitudinally thereof coal entering into the housing end proximate to the coal pile.

7. A conveyor `for removing piled coal and the like comprising a round bottom housing adapted for positioning at one end below the pile and extending away therefrom into the open, a feed screw extending lengthwise through the housing, the housing exteriorly of the pile being provided with walls extending upwardly above the feed screw, opposed retainer means arranged in pairs, spaced apart lengthwise of each other, and carried upon the walls of the housing interiorly thereof in partial overlapping relation to the feed screw and cooperating with the housing round bottom to confine rotation of the feed screw about 8 a fixed axis wherebyy to propel longitudinally thereof coal received within the housing end proximate to the coal pile.

BRADFORD B. NELSON. JAMES H. NELSON.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 843,676 Gustavsen Feb. 12, 1907 985,436 Mount Feb. 28, 1911 1,794,326 Sierer Feb, 24, 1931 1,828,268 Wilkes Oct. 20, 1931 2,279,201 Kozack et al. Apr. 7, 1942 2,369,370 Scholl Feb. 13, 1945 2,408,952 Raney Oct. 8, 1946 2,412,121 Bradshaw Dec. 3, 1946 2,418,540 Bressler Apr. 8, 1947 FOREIGN PATENTS Number Country Date 113,436 Great Britain Oct. 17, 1918 

